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Venting Plumbing for Remodel - Upside down P-Traps Possible?

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I'm renovating a home that never had plumbing incomplete build if you will...and repurposing some of the rooms that weren't originally built with plumbing. The place is two-story but only about 1,500 sq. ft,, one bath, laundry, and kitchen for plumbing needs. I think it would be easiest to vent the plumbing through a first floor side wall rather than through the upstairs roof....and I prefer not to have roof penetrations. I don't have to comply with any city codes, as I'm in the country, but I do want the system to work properly!

All of the plumbing is on the first floor and the home is on an on-site septic system. Using the drain for the shower as an example, can I extend the vent pipe up, say 12-24" from the elevation of the drain and then 180 the vent back down through the floor plate to a common vent pipe running under the pier and beam home for the bathroom sink, toilet, wash machine, and kitchen sink? The common vent pipe under the home would have a single riser in an exterior wall and vent about 8' high on the east side of the house. The point of the upside down P-trap for each plumbing fixture would be to prevent water from rising from the fixture and up into the vent line.

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